In recent years tablet-type personal computers (tablet PCs) having a touch-screen liquid crystal display and not having a physical keyboard have become rapidly more popular. A tablet PC is easy to carry around and is easy to operate because data can be entered using a touch screen.
Such a tablet PC, however, does not have a physical keyboard, and so it may affect the entry operation of the data containing long sentences, for example. Then a convertible tablet-type personal computer (convertible PC) has been proposed, including a display part having a display that is rotatable by 360 degrees beyond 180 degrees relative to a main body part having a keyboard. Since the convertible-type PC can be used in two ways including a normal laptop personal computer (laptop PC) and a tablet PC, this type of PC offers excellent convenience to users, and Japanese Patent Application Laid-Open No. 2013-155874, for example, discloses a two-axle structured hinge mechanism that can be used for such a structure.